JP2006143272A - Packaging bag and package using it - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a good packaging bag capable of taking out a packaged article which tends to stick the inner face of the packaging bag and to lose a shape of the outer surface, to the outside of the bag with an equal appearance to that before packaging, and in particular, to provide a packaging bag which is excellent in stiffness of a film constituting the packaging bag, and is good in such properties required when an article is packaged as heat seal properties, pinhole resistance, piercing resistance, barrier properties preventing oxygen gas, steam or the like from permeating, preservation properties in circulation, and heat resistance, and to provide a package using it. <P>SOLUTION: A laminated material manufactured by making a heat seal layer overlie at least one face of a substrate film is manufactured into a bag to provide a bag-like container main body, and the tapered bending rigidity of the whole laminated material is 0.43-0.80 g cm. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a packaging bag and a packaging body using the same. It is a packaging bag used to reheat cooked foods, and since the film has excellent flexibility, the contents to be adhered to the surface of the bag are difficult to adhere and the outer surface shape tends to collapse before packaging. In addition to being able to be taken out of the bag smoothly with the same appearance, it also has good slipperiness, surface roughness, distribution storage, heat sealability, pinhole resistance, puncture resistance required for packaging of goods. The present invention relates to a packaging bag having a barrier property that prevents permeation of oxygen gas, water vapor, and the like and can withstand heat treatment associated with processing such as retort processing and the package.

Conventionally, in order to fill and package various articles, plastic substrates, paper substrates, metal foils, etc. are used, and these are arbitrarily laminated, and various packaging materials have been developed and proposed. Yes.
These packaging materials are usually provided with a heat seal layer at the innermost layer, with the heat seal layers facing each other, and the peripheral edges thereof are heat sealed. Manufacturing various types of packaging containers, and filling and packaging various contents such as foods and drinks, pharmaceuticals, cosmetics, detergents, chemicals, miscellaneous goods, etc. from the opening of the packaging container Thus, various types of packaged products are manufactured.
Among them, retort pouches generally close the mouth of a container filled with a prepared material while evacuating the air as much as possible, and heat the mouth to seal the plastic while melting to produce a sealed package, For example, a normal retort kettle is used for the sealed package, for example, temperature, 110 ° C. to 140 ° C., preferably about 120 ° C., pressure, 1 to 3 kgf / cm ² , preferably 2 About 1 kgf / cm ² , time, 20 to 60 minutes, preferably about 30 minutes by heating and pressurizing, a retorted package product can be manufactured. is there.

In addition, the packaging material that constitutes the retort pouch has heat resistance, shock absorption, prevention of corrosion of aluminum foil, biaxially stretched polyethylene terephthalate film that has gloss and printing effects, and impact resistance and self-supporting properties (standing up). Uses a laminate in which an axially stretched nylon film, an aluminum foil that blocks light, oxygen, and water vapor, and a heat-sealable film made of an unstretched polyolefin resin film are laminated via a reaction-curable heat-resistant adhesive layer. ing.
For this reason, as a retort pouch, the quality of the contents is maintained for a long time at normal temperature circulation, the taste is not deteriorated, and heat resistance, cold shock resistance, barrier properties, heat sealability, hygiene, etc. Required.

As a conventional retort pouch, a retort pouch formed by making a packaging material obtained by laminating a polyethylene terephthalate film, a biaxially stretched nylon film, an aluminum foil, and an unstretched polypropylene film in this order is described (for example, , See Patent Document 1).
In addition, as a conventional retort pouch, a base layer (polyethylene terephthalate film, etc.), an intermediate layer (aluminum foil, etc.), and a sealant layer (unstretched polypropylene film composed of an ethylene / propylene / block copolymer resin) are sequentially provided. A retort sterilizable packaging bag made of a laminated film is described (for example, see Patent Document 2).
Japanese Patent No. 2839747 JP 11-79191 A

  However, in the conventional packaging bag as shown above, the inner surface of the heat seal layer in contact with the package is smooth and lacks slipperiness, and the outer surface adheres to the bag like a boiled egg in the bag. If the package to be packaged is easily put into a packaging bag and sealed, it is sealed and packaged in a state where the package and the inner surface of the bag are in close contact, and then the obtained sealed package is boiled or retorted. The air remaining in the bag is compressed by the pressurization, and the packaged item and the bag inner surface are in close contact with each other, and the packaged item adheres to the bag inner surface due to the heat coagulation of the packaged product. When the package is taken out of the bag, the outer surface of the package is peeled off and loses its shape. In some cases, even the yolk is exposed, and the consumer cannot take out the package smoothly. The appearance and flavor of the product itself are also impaired. We commercial value there has been a problem of a decrease.

  An object of the present invention is to provide a good packaging bag that can be taken out of the bag with the same appearance as before packaging even if it is an article to be packaged that easily adheres to the inner surface of the packaging bag and whose outer surface shape tends to collapse. In particular, it excels in the strain of the film that constitutes the packaging bag, as well as the heat sealability, pinhole resistance, puncture resistance, barrier properties that prevent permeation of oxygen gas, water vapor, etc. It is intended to provide a packaging bag that has storability and can withstand heat treatment accompanying processing such as retort processing and a package using the same.

  Therefore, in order to solve the above problems, the packaging bag of the present invention comprises a bag-like container body formed by bag-making a laminated material in which a heat seal layer is laminated on at least one surface of a base film, and The taper bending stiffness of the entire laminated material is 0.43 g · cm to 0.80 g · cm.

  The packaging bag of the present invention is characterized in that a barrier layer and / or a pinhole-resistant layer is provided as an intermediate layer between the base film layer and the heat seal layer.

  The packaging bag of the present invention is characterized in that the laminated material is laminated via an adhesive layer for dry lamination.

  The packaging bag of the present invention is characterized in that an anti-blocking powder is contained on the inner surface of the bag-like container body.

  In the packaging bag of the present invention, the base film is made of a biaxially stretched resin film.

  In the packaging bag of the present invention, the barrier layer constituting the packaging material is composed of a metal foil or a structure in which a metal vapor deposition film or an inorganic oxide vapor deposition film is provided on one surface of the base film. And

  Moreover, the packaging bag of this invention WHEREIN: The pinhole-resistant layer which comprises a packaging material consists of a biaxially stretched polyamide-type resin film, It is characterized by the above-mentioned.

  Moreover, the packaging bag of this invention WHEREIN: The heat seal layer which comprises a packaging material consists of an unstretched polyolefin resin film, It is characterized by the above-mentioned.

Moreover, the package of the present invention is obtained by filling and packaging the contents in the above-described packaging bag, and under conditions of a temperature of 110 ° C. to 130 ° C., a pressure of 1 to 3 kgf / cm ² · G, and a time of 20 minutes to 60 minutes. The heat-pressurization sterilization process which becomes is characterized.

  Moreover, the package of this invention WHEREIN: The said content contains a boiled egg, It is characterized by the above-mentioned.

  Moreover, the package of this invention WHEREIN: The said content is an oden-style boiled food, It is characterized by the above-mentioned.

According to the packaging bag according to the present invention, the flexibility of the film constituting the packaging bag is superior to that of the conventional bag, the packaged item is less likely to adhere to the inner surface of the bag, and the packaged item is Even if it touches the inner surface once, it can be easily removed from the surface of the bag, and the consumer can smoothly remove the package from the bag, and the outer surface of the package is not scratched or peeled off. The outer shape of the object does not collapse and is excellent in commercial value.
In addition, the packaging bag of the present invention can be provided with an intermediate layer between the base film layer and the heat seal layer, whereby the packaging bag is further pin-hole resistant, Functions such as puncture resistance, barrier properties that prevent permeation of oxygen gas, water vapor, and the like can be added.
In addition, good slipperiness, surface roughness, distribution storage stability, heat sealability, pinhole resistance, puncture resistance, barrier properties that prevent permeation of oxygen gas, water vapor, etc., required for packaging of articles. The packaging bag which can endure the heat processing accompanying processing, such as a retort process, and its package can be provided.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a cross-sectional view showing an example of a laminate constituting the packaging bag of the present invention. The laminated body 10 has a basic structure in which the base film layer 1 and the heat seal layer 2 are laminated from the outside.
In addition, the taper bending stiffness of the entire laminated body 10 constituting the packaging bag needs to be 0.43 g · cm to 0.80 g · cm, which makes the film excellent in flexibility and on the inner surface of the bag. There is an advantage that a package to be attached easily can be taken out of the bag, the outer surface of the package is not scratched or peeled, and the outer shape of the package is not broken.

Fig.2 (a) is sectional drawing which shows an example of the laminated body of another aspect which comprises the packaging bag of this invention. The laminate 10 has a basic structure in which the base film 1, the intermediate layer 3, and the heat seal layer 2 are laminated from the outside.
And FIG.2 (b) is the laminated body 10 which laminated | stacked the base film 1, the pinhole-resistant layer 31 which is an intermediate | middle layer, and the heat seal layer 2 from the outer side.
FIG.2 (c) is the laminated body 10 which laminated | stacked the base film 1, the barrier layer 32, such as oxygen and water vapor | steam which are intermediate layers, and the heat seal layer 2 from the outer side.
FIG. 2D shows a laminate 10 in which a base film 1, a pinhole resistant layer 31, which is an intermediate layer, a barrier layer 32, and a heat seal layer 2 are laminated from the outside.
In addition, it can laminate | stack between each layer of said laminated body 10 through an adhesive layer as needed. Moreover, a printing layer can be formed on the front surface or the back surface of the base film 1.
A packaging bag employing the above layer structure can improve the quality preservation of the contents, the distribution safety, and the like.

  FIG. 3 is a conceptual diagram showing an example of the packaging bag 20 of the present invention. As shown in FIG. 3, the packaging bag of this invention uses the laminated body 10 manufactured above, makes the surfaces of the heat seal layer which becomes the innermost layer face each other, and folds them or two of them. A bag body can be formed by stacking the two, and further heat sealing the peripheral edge portion to provide a seal portion.

  FIG. 4 is a conceptual diagram showing an example of the package 30 of the present invention. As shown in FIG. 4, the packaging body according to the present invention is filled with the contents from the opening above the packaging bag of FIG. 3, and then the opening is heat sealed to seal the upper end. A packaged product formed by using the packaging container according to the present invention can be manufactured.

As the base film layer 1 of the present invention, when constituting a packaging bag, it becomes a basic material, and after packaging, impact resistance, heat for protecting the packaging material and contents from external physical impact It is possible to use a resin film or sheet having heat resistance that can withstand sealing and printability.
Specifically, for example, polyester resin, polyamide resin, polyaramid resin, polyolefin resin, polycarbonate resin, polystyrene resin, polyacetal resin, fluorine resin, etc. A resin film or sheet, or the like can be used.
And as said resin film or sheet, any of an unstretched film or a stretched film stretched in a uniaxial direction or a biaxial direction can be used, and in particular, it is a biaxially stretched film. Is preferable because of excellent heat resistance that can withstand boiling and retorting.
The thickness of the film is about 5 to 100 μm, preferably about 10 to 50 μm.
Further, if necessary, a metal such as aluminum or an inorganic material such as aluminum, alumina oxide or silicon oxide may be vapor-deposited on these base films.
In the present invention, for the above-mentioned base film, for example, a desired printing pattern such as a character, a figure, a symbol, a pattern, a pattern, or the like is printed by offset printing or gravure printing or flexographic printing using a normal ink composition. In addition, printing may be performed on the front surface or the back surface of the base film as necessary by a normal printing method such as letterpress printing, silk screen printing, or the like.

Next, in the present invention, the material constituting the heat seal layer 2 will be described. As such a layer, any material can be used as long as it can withstand retort processing and can be melted by heat and fused to each other.
Specifically, for example, low-density polyethylene film, medium-density polyethylene film, high-density polyethylene film, linear low-density polyethylene film, polypropylene film, ethylene-vinyl acetate copolymer resin film, ionomer-resin film, ethylene-acrylic Acid copolymer resin film, ethylene-ethyl acrylate copolymer resin film, ethylene-methacrylic acid copolymer film, ethylene-propylene copolymer film, methylpentene resin film, polybutene resin film, acid-modified polyolefin resin, etc. An unstretched film of polyolefin resin can be used.
The thickness of the film is 10 to 300 μm, preferably about 20 to 100 μm.

Furthermore, in the present invention, the above heat seal layer 2 has an average surface roughness Ra of 0.03 μm to 0.5 μm on the inner surface in contact with an object to be packaged, and easily adheres to the inner surface of the bag. When taking out a packaged object out of a bag, it is preferable at the point that the external shape of a packaged product does not collapse, and it is more preferable that it is 0.05 micrometer-0.4 micrometer.
If the average surface roughness Ra is less than 0.03 μm, it tends to adhere to the inner surface of the bag, resulting in inferior slipperiness. Therefore, if the average surface roughness Ra exceeds 0.5 μm, Since the surface is damaged, it is not preferable.
Moreover, it is preferable that a static friction coefficient and a dynamic friction coefficient exist in the range of 0.01-0.2, and it is more preferable that a static friction coefficient and a dynamic friction coefficient are 0.18 or less.
When the coefficient of static friction and the coefficient of dynamic friction exceed 0.2, blocking prevention property and slipperiness are insufficient, and the packaged article adheres to the surface of the bag, and the packaged article cannot be smoothly taken out of the bag. This is not preferable because the outer surface is partially peeled off and the appearance and flavor of the packaged article are deteriorated.

In the present invention, the inner surface in contact with the article to be packaged contains an anti-blocking powder, has no adhesiveness, and can further improve the anti-blocking property and slipperiness. It is preferable in that the product can be easily taken out.
Specifically, it is preferable in view of the above starch-based powder having a particle size of 5~10μm position is antiblocking powder (e.g. Nikkari powder, etc.) is sprayed about ^{10g / m 2 ~30g / m 2} .
In addition to the above effects, the anti-blocking powder has a function of a lubricant when it comes into contact with the machine in the packaging bag processing process and the content filling process. It is also preferable in that it is possible to prevent poor positioning, poor running, and poor folding.
On the other hand, when the application amount of the anti-blocking powder is less than 10 g / m ² , the function of easily taking out the package is not expressed, and when it exceeds 30 g / m ² , the appearance of the packaging bag is poor. This is not preferable.

Next, in the present invention, as a material constituting the intermediate layer 3 forming the laminate, for example, a coating of polyvinylidene chloride resin having a barrier property against oxygen, water vapor, etc., polyvinyl alcohol, ethylene-vinyl acetate Polymer film saponified resin film or sheet, film deposited on inorganic material such as aluminum, alumina oxide, silicon oxide, etc., colorant such as pigment to resin, other desired additives and kneading Various colored resin films or sheets having light-shielding properties formed into a film can be used.
These materials can be used alone or in combination. The thickness of the above-mentioned film or sheet is arbitrary, but usually about 5 to 200 μm, more preferably about 10 to 100 μm.

Specifically, in the present invention, examples of the resin film that supports the above-described deposited film include polyester resin films such as polyethylene terephthalate, polyamide resin films such as various nylons, polyethylene resins, and polypropylene resins. Resin, cyclic polyolefin resin, polystyrene resin, acrylonitrile-styrene copolymer (AS resin), acrylonitrile-butadiene-styrene copolymer (ABS resin), polyolefin film such as polybutene resin film, polyvinyl chloride resin, polycarbonate Bonate resin, polyimide resin, polyamideimide resin, polyaryl phthalate resin, silicone resin, polysulfone resin, polyphenylene sulfide resin, polyethersulfone resin, polyurethane resin, cell Over scan resins, poly (meth) acrylic resins, polyvinylidene chloride film, acetal resin film, fluorine-based resin, it is possible to use other like.
In the present invention, it is particularly preferable to use a film or sheet of polypropylene resin, polyester resin, or polyamide resin.

Next, in the present invention, a method for forming a metal or inorganic oxide vapor deposition film constituting the barrier layer will be described. Examples of such a method include physical vapor deposition, sputtering, ion plating, and the like. Phase growth method (Physical Vapor Deposition method, PVD method), or Chemical Vapor Deposition method such as Plasma Chemical Vapor Deposition method, Thermal Chemical Vapor Deposition method, Photochemical Vapor Deposition method (Chemical Vapor Deposition method, CVD method) Etc.
In the present invention, a method for forming a vapor deposition film of metal or inorganic oxide will be described in detail. Using the metal or metal oxide as described above as a raw material, this is heated and vapor deposited on a flexible film. Vacuum deposition method or oxidation reaction deposition method that uses metal or metal oxide as raw material, oxidizes by introducing oxygen gas etc. and deposits on flexible film, and plasma that further assists oxidation reaction with plasma A vapor deposition film can be formed using an auxiliary oxidation reaction vapor deposition method or the like.
In the present invention, when a silicon oxide vapor deposition film is formed, the vapor deposition film can be formed by a plasma chemical vapor deposition method using organosiloxane as a raw material.

In the present invention, the pinhole-resistant layer constituting the intermediate layer 3 exhibits excellent properties in mechanical, physical, chemical, etc., has excellent strength, and further has heat resistance, resistance to resistance. A film or sheet having excellent physical properties such as pinhole property and puncture resistance can be used.
Specifically, as a material for the layer imparting pinhole resistance, strong resin such as polyethylene resin, polypropylene resin, polyester resin, polyamide resin, polyaramid resin, polycarbonate resin, polyacetal resin, fluorine resin, etc. A film or sheet can be used.
And as said resin film or sheet, any of an unstretched film or a stretched film stretched in a uniaxial direction or a biaxial direction can be used. It is preferable in terms of excellent heat resistance.
In the present invention, the thickness of the resin film or sheet may be a thickness that can be kept to the minimum necessary for strength, pinhole resistance, puncture resistance, rigidity, etc., and is too thick. When the film is too thin, the strength, puncture resistance, rigidity, etc. are undesirably lowered.
The thickness of the film is about 5 to 100 μm, preferably about 6 to 50 μm.

Next, in the present invention described above, a method for producing a laminate using the above materials will be described. As such a method, a method for laminating a normal packaging material, for example, wet lamination is used. , Dry lamination method, solventless dry lamination method, extrusion lamination method, T-die extrusion molding method, co-extrusion lamination method, inflation method, co-extrusion inflation method, etc. be able to.
And in this invention, when performing said lamination | stacking, if necessary, pre-treatments, such as a corona treatment, an ozone treatment, a frame treatment, etc., can be given to a film.
As the adhesive layer in the present invention, for example, polyester-based, isocyanate-based (urethane-based), polyethyleneimine-based, polybutadiene-based, organic titanium-based anchor coating agents, polyurethane-based, polyacrylic-based, polyester, etc. It is preferable to use an anchor coating agent such as a laminating adhesive such as a laminating system, an epoxy system, a polyvinyl acetate system, a cellulose system, or the like, and an adhesive.

The range of the total thickness of the laminated body used by this invention can be used in the range of about 5 micrometers-200 micrometers, and the range of about 40 micrometers-80 micrometers can be used more preferably.
The taper bending stiffness of the entire laminate obtained as described above needs to be 0.43 g · cm to 0.80 g · cm, which makes the film excellent in flexibility and the inner surface of the bag. There is an advantage that even a packaged item that easily adheres to the bag can be easily taken out of the bag.
If it is less than 0.43 g · cm, wrinkles are likely to occur in the film processing step, and this is not preferable in terms of workability. If it exceeds 0.80 g · cm, the packaged article adheres to the inner surface of the bag. This is not preferable in that it is easy to remove from the bag.

Next, in the present invention, a method for making a bag using the laminate as described above will be described. Using the laminate obtained as described above, the surface of the heat seal layer of the inner layer is used. Can be folded, or the two sheets can be overlapped, and the peripheral edge can be heat sealed to provide a seal portion to form a bag.
Thus, as the bag making method, the above laminated body is folded with the inner layer surfaces facing each other, or the two sheets are overlapped, and the peripheral edge of the outer periphery is, for example, a side sheet. Seal type, two-sided seal type, three-sided seal type, four-sided seal type, envelope-sealed seal type, jointed seal type (pillar seal type), pleated seal type The various types of packaging containers according to the present invention can be manufactured by heat sealing in the form of a heat sealing such as a flat bottom sealing type, a square bottom sealing type, or the like.
In addition, for example, self-supporting packaging bags (standing pouches), spout pouches and the like can be manufactured. Further, in the present invention, a tube container, an in-mold label, a cup is used by using the above laminated material. A cover material for a product can also be manufactured.
In the above, as the heat seal method, for example, a bar seal, a rotary roll seal, a belt seal, an impulse seal, a high frequency seal, an ultrasonic seal and the like are known. It can be done by the method.
In the present invention, a spout such as a one-piece type, a two-piece type, or the like, or a zipper for opening and closing can be arbitrarily attached to the packaging container as described above.

In the present invention, the packaging bag produced as described above can seal and sterilize a wide variety of foods and the like.
Examples of contents that are particularly suitable for filling and sealing the above packaging bags include curry, stew and other retort foods, seasonings such as miso, kneaded products such as konjac, chikuwa, koji, and smoked ham and sausages. Products, cooked foods such as meatballs, hamburgers and marvo tofu, processed fishery products, pickles, boiled foods, and other food and drinks.
In the present invention, among the above contents, chicken eggs, quail eggs, duck eggs and other boiled eggs, fish strips, shell strips, tofu, etc. Even an object can be smoothly taken out from the bag with the appearance before filling.
Here, boiled eggs are those that are peeled off after being heated and solidified in the state of being shelled.

In the present invention, the packaging body filled with the above contents in the packaging bag produced as described above is placed in a retort kettle, for example, at a temperature of 110 ° C. to 130 ° C., and a pressure of 1 to 3 kgf / cm ² · G. A packaged product with excellent quality retention can be obtained by heat and pressure sterilization treatment under conditions of 20 minutes to 60 minutes.

Next, the present invention will be described in more detail according to specific examples.
First, as a base material layer 1, a vapor deposition film (product name “1011HG”, manufactured by Toray Film Processing Co., Ltd.) in which a vapor deposition layer of aluminum having a thickness of 100 mm was formed on one side of a biaxially stretched polyethylene terephthalate film having a thickness of 12 μm was prepared.
On the surface of the aluminum vapor-deposited film on which the vapor-deposited layer is not formed, a desired printed pattern consisting of letters, symbols, figures, etc. in five colors as a print layer ("Krios" manufactured by Inktec Co., Ltd.) It formed by the gravure printing method.
Further, on the printed surface formed as described above, as an adhesive layer, a two-component curable polyurethane adhesive (main agent “LX703” / curing agent “KR90”, manufactured by Mitsui Takeda Chemical Co., Ltd.) 3.5 g / m ² (dry state) ) And a 15 μm biaxially stretched nylon film (product name “Bonyl QC”, manufactured by Kojin Co., Ltd.) was laminated by a dry lamination method to produce a laminated film.
Next, 3.5 g / m ² (dry state) of polyurethane adhesive was applied to the biaxially stretched nylon film surface of the laminated film obtained above, and an unstretched linear low-density polyethylene film having a thickness of 60 μm ( The product name “RS” (manufactured by Showa Denko) is sequentially laminated by the dry lamination method, and the layer structure is (outer surface) biaxially stretched polyethylene terephthalate film layer 12 μm / printing ink composition layer / adhesive layer / biaxially stretched nylon. A laminated sheet of Example 1 according to the present invention having a film layer of 15 μm / adhesive layer / unstretched linear low density polyethylene film layer of 60 μm (inner surface) was prepared and aged at 40 ° C. for 3 days.
In addition, about 30 g / m ² of starch-based powder having a particle size of about 10 μm was sprayed as an anti-blocking powder on the inner surface side of the laminated sheet obtained above.
Next, two sheets of 230 mm × 170 mm are cut out using the laminated sheet obtained above, and unstretched linear low-density polyethylene films are arranged so as to face each other, with two vertical sides and one horizontal side of 10 mm. A packaging bag was obtained by thermocompression bonding under conditions (conditions 200 ° C., 2 kg / cm ² , 0.5 seconds).
Next, as an oden-style simmered food, a shelled egg, kelp, konjac, burdock roll, bamboo ring, radish, deep-fried satsuma, ganmodori (240g), salt, A seasoning liquid (240 cc) containing soy sauce, sake, dashi stock, etc. was filled, and the upper seal part was pressed and manufactured to produce a semi-finished product.
Next, heat and pressure sterilization was performed in a steam retort kettle at a temperature of 120 ° C. and a pressure of 180 kPa for 30 minutes to obtain a package body subjected to the heat and pressure sterilization treatment according to the present invention.
The packaging bag produced above has good film flexibility, so that the eggs can be smoothly taken out of the bag with a boil and the appearance equivalent to that before packaging can be obtained. It was excellent in pinhole property, puncture resistance, barrier property to prevent permeation of oxygen gas, water vapor and the like, heat resistance, slip property, distribution preservability, hygiene, and quality preservability.

In Example 1, instead of the unstretched linear low-density polyethylene film layer, the heat seal layer was an unstretched polypropylene film having a thickness of 60 μm and a smooth surface (product name “RXC21” manufactured by Tosero Co., Ltd.), In the same manner as in Example 1, layer structure, biaxially stretched polyethylene terephthalate film layer 12 μm / printing ink composition layer / adhesive layer / biaxially stretched nylon film layer 15 μm / adhesive layer / unstretched polypropylene film layer 60 μm (inner surface ) Was produced. In addition, about 30 g / m ² of starch-based powder having a particle size of about 10 μm was sprayed as an anti-blocking powder on the inner surface side of the laminated sheet obtained above.
Furthermore, using this laminated sheet, a packaging bag was produced in the same manner as in Example 1, and after filling the contents, the package was sealed. Thereafter, heat and pressure sterilization was performed under the same heat and pressure conditions as in Example 1 to obtain a package according to Example 2.
The packaging bag produced above has good film flexibility, so that the eggs can be smoothly taken out of the bag with a boil and the appearance equivalent to that before packaging can be obtained. It was excellent in pinhole property, puncture resistance, barrier property to prevent permeation of oxygen gas, water vapor and the like, heat resistance, slip property, distribution preservability, hygiene, and quality preservability.

[Comparative Example 1]
In Example 2, instead of the biaxially stretched nylon film layer of the intermediate layer, the same as Example 2 except that a 15 μm biaxially stretched nylon film (product name “ONMBCRT”, manufactured by Unitika Co., Ltd.) was used. A laminated sheet having a layer structure of biaxially stretched polyethylene terephthalate film layer 12 μm / printing ink composition layer / adhesive layer / biaxially stretched nylon film layer 15 μm / adhesive layer / unstretched polypropylene film layer 60 μm (inner surface) Produced. In addition, about 30 g / m ² of starch-based powder having a particle size of about 10 μm was sprayed as an anti-blocking powder on the inner surface side of the laminated sheet obtained above.
Furthermore, using this laminated sheet, a packaging bag was produced in the same manner as in Example 2, and after filling the contents, the package was sealed. Thereafter, heat and pressure sterilization was performed under the same heat and pressure conditions as in Example 2 to obtain a package according to Comparative Example 1.

[Comparative Example 2]
In Example 2, instead of the biaxially stretched nylon film layer of the intermediate layer, a 15 μm biaxially stretched nylon film (product name “ONMBCRT”, manufactured by Unitika Co., Ltd.) with a film strain was used, and the laminated sheet obtained above was used. Except that the antiblocking powder is not sprayed on the inner surface side, the layer structure, biaxially stretched polyethylene terephthalate film layer 12 μm / printing ink composition layer / adhesive layer / biaxially stretched nylon film layer in the same manner as in Example 2. A laminated sheet of 15 μm / adhesive layer / unstretched polypropylene film layer 60 μm (inner surface) was produced. Further, using this laminate, a packaging bag was prepared in the same manner as in Example 2, and after filling the contents, the package was sealed. Thereafter, heat and pressure sterilization was performed under the same heat and pressure conditions as in Example 2 to obtain a package according to Comparative Example 2.

[Performance evaluation results]
Film strain, surface roughness, slipperiness, adhesion to contents, heat seal strength, impact strength, and impact resistance were evaluated as follows. The evaluation results are summarized in Table 1.

(1) Taper Bending Stiffness Regarding the stiffness (softness) of the laminated film constituting the packaging bags according to the above examples and comparative examples, a pure bending tester JTC-911BT (model name) manufactured by SMT Co., Ltd. is used. Evaluation was made at a curvature change rate of 0.1 / cm / sec, a clamp interval of 1.0 cm, and a maximum curvature of 2.5 cm ⁻¹ . The test piece was 100 mm × 100 mm. The measurement results are as shown in Table 1 below.

(2) Surface roughness The surface roughness (Ra) of the heat-sealable film constituting the packaging bag used in the above examples and comparative examples is a stylus type surface roughness in accordance with JIS-B-0651 (1976). Measured with a measuring instrument (Tokyo Seimitsu Co., Ltd., SURFCOM), the measurement conditions were: stylus tip radius of curvature 5 μm, cutoff wavelength 0.25 mm, cutoff type 2CR (phase compensation), measurement speed 0 .3 mm / second, the measurement direction was the film MD direction, and the measurement length was 4 mm. The measurement results are as shown in Table 1 below.

(3) Coefficient of friction Using the heat-sealable film constituting the packaging bag used in the above examples and comparative examples, the surface of the heat-sealable film (the side that becomes the inner surface of the packaging bag) and metal (in accordance with JIS K7126) The coefficient of friction with the surface was measured with a static friction coefficient of μ0 and a dynamic friction coefficient of μ. The measurement results are as shown in Table 1 below.

(4) Adhesiveness to contents Eggs (20 pieces) were stored in the packaging bags used in the above examples and comparative examples with the shells peeled off as the contents. Each was evacuated and sealed, and the inner surface of the packaging bag was adhered to the surface of the egg with a boil.
Next, heat and pressure sterilization was carried out under the conditions of 120 ° C., 180 kPa, and 30 minutes, respectively. Thereafter, the resulting package was opened, the egg was removed with a boil, and the presence or absence of the boiled egg with the outer surface peeled was confirmed. The results are shown in Table 1. In Table 1, the number of eggs per peeled nail / n (n: the number of eggs in a pail in a bag) is shown.

(5) Heat seal strength The packaging bags used in the above examples and comparative examples were filled with the contents and sealed, and heat and pressure sterilization was performed under conditions of temperature and pressure of 120 ° C. and pressure of 180 kPa for 30 minutes. Thereafter, the heat seal strengths in the MD direction and the TD direction were measured.
Here, the MD direction is a film feeding direction when a resin composition mainly composed of a propylene-ethylene block copolymer is extruded, and the TD direction is a direction perpendicular to the MD direction.
The heat seal strength in the MD direction is measured by cutting out a test piece including a heat seal portion on the vertical side of the packaging bag with a width of 15 mm and pulling it in parallel with the MD direction.
Further, the heat seal strength in the TD direction is measured by cutting a test piece including a heat seal portion on the lateral side with a width of 15 mm and pulling the test piece in parallel with the TD direction.
The heat seal strength and the laminate strength were measured at a tensile speed of 300 mm / min using a tensile tester (Orientec). The results are shown in Table 1. In Table 1, the heat seal strength per 15 mm (unit: N / 15 mm) is shown.

(6) Impact strength After the packaging bags used in the above examples and comparative examples are filled and sealed, and subjected to heat and pressure sterilization at a temperature of 120 ° C. and a pressure of 180 kPa for 30 minutes. The laminated film constituting the packaging bag was used, and was cut as a test piece with scissors in a size of 100 mm × 100 mm, and the energy required for breaking the test piece was measured using a film impact tester (manufactured by Toyo Seiki). At this time, the impact head spherical surface and the capacity are usually 1 inch × 18 kg · cm. The results are shown in Table 1.

(7) Bag drop test The packaging bags used in the above examples and comparative examples were filled with the contents and sealed, and subjected to heat and pressure sterilization under the conditions of temperature and pressure of 120 ° C. and pressure of 180 kPa for 30 minutes. Thereafter, it was refrigerated at 3 ° C. for one week. The sample after refrigerated storage was subjected to 30 vertical drops continuously from a height of 150 cm on the concrete floor with the surface of 230 mm facing down, and then the presence of broken bags was checked. The results are shown in Table 1. In Table 1, the number of broken bags / n (n: the number of bags used in the bag drop test) is described.

(Experimental result)

As a result, as shown in Table 1, the packaging bags of Examples 1 and 2 are excellent in flexibility of the film, so that even if the contents are easily attached to the inner surface of the packaging bag and easily damaged from the outside, the packaging bag It could be taken out of the bag with the same appearance as before.
In the above, since the lamination sheet which comprises the packaging bag of Example 1 is excellent in the softness | flexibility of a film, and excellent in the slipperiness of the inner surface of a packaging bag, it was able to take out out of a bag more smoothly.
In addition, the packaging bags of Examples 1 and 2 have no film odor and are excellent in heat seal strength, laminate strength, tear strength, and impact resistance. It was excellent in properties.
Since the packaging bags of Comparative Examples 1 and 2 have a strain on the film and the taper bending stiffness is greater than or equal to a predetermined value, the contents easily adhere to the inner surface of the packaging bag regardless of the presence or absence of blocking prevention powder spraying, When taken out of the bag, the contents peeled off at the part where the inner surface of the packaging bag was stuck, and the yolk appeared, which was inferior in the packaging bag's contents storage suitability, filling suitability, and distribution of the package. .

It is sectional drawing which shows an example of the laminated body 10 which comprises the packaging bag of this invention. It is sectional drawing which shows an example of the laminated body 10 of another aspect which comprises the packaging bag of this invention. It is a conceptual diagram which shows an example of the packaging bag 20 of this invention. It is a conceptual diagram which shows an example of the package 30 of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Base film layer 2 Heat seal layer 3 Intermediate layer 31 Pinhole-resistant layer 32 Barrier layer 4 Seal part 5 Upper end part 6 Contents 10 Laminated body 20 Packaging bag 30 Packaging body

Claims (11)

  It comprises a bag-like container body formed by bag-making a laminated material in which a heat seal layer is laminated on at least one surface of a base film, and the taper bending stiffness of the whole laminated material is 0.43 g · cm to 0 A packaging bag characterized by being 80 g · cm.   The packaging bag according to claim 1, wherein a barrier layer and / or a pinhole-resistant layer is provided as an intermediate layer between the base film layer and the heat seal layer.   The packaging bag according to claim 1, wherein the laminated material is laminated through an adhesive layer for dry lamination.   The packaging bag according to any one of claims 1 to 3, wherein an anti-blocking powder is contained on an inner surface of the bag-like container body.   The packaging bag according to any one of claims 1 to 4, wherein the base film is made of a biaxially stretched resin film.   3. A packaging bag, wherein the barrier layer according to claim 2 comprises a metal foil or a structure in which a metal vapor deposition film or a vapor deposition film of an inorganic oxide is provided on one surface of a base film.   The packaging bag according to claim 2, wherein the pinhole-resistant layer is made of a biaxially stretched polyamide resin film.   The packaging bag according to any one of claims 1 to 7, wherein the heat seal layer is made of an unstretched polyolefin resin film. The packaging bag according to any one of claims 1 to 8 is filled and packed with the contents, and the temperature is 110 ° C to 130 ° C, the pressure is 1 to 3 kgf / cm ² · G, and the time is 20 minutes to 60 minutes. A package characterized by being subjected to a heat and pressure sterilization treatment.   The package according to claim 9, wherein the contents include a boiled egg. The package according to claim 9, wherein the content is an oden-style boiled food.

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